DNA analysis

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DNA analysis reveals likely pathogens that killed Napoleon’s army

Biology, DNA analysis, forensic archaeology, history, Napoleon Bonaparte, pathogens, Science / /

State-of-the-art methodologies

Painting of Napoleon's army.

Rascovan and his co-authors note in their paper that the 2006 study relied upon outdated PCR-based technologies for its DNA analysis. As for the virus family detected in the Kalingrad dental pulp, they argue that those viruses are both ubiquitous and usually asymptomatic in humans—and thus are unlikely to be the primary culprits for the diseases that wiped out the French army. So Rascovan’s team decided to use current state-of-the-art DNA methodologies to re-analyze a different set of remains of Napoleonic soldiers who died in Vilnius.

“In most ancient human remains, pathogen DNA is extremely fragmented and only present in very low quantities, which makes it very difficult to obtain whole genomes,” said Rascovan. “So we need methods capable of unambiguously identifying infectious agents from these weak signals, and sometimes even pinpointing lineages, to explore the pathogenic diversity of the past.”

An 1812 report from one of Napoleon’s physicians, J.R.L. de Kirckhoff, specifically noted typhus, dysentery, and diarrhea after the soldiers arrived in Vilnius, which he attributed to large barrels of salted beets the starving troops consumed, “greatly upsetting us and strongly irritating the intestinal tract.” Rascovan et al. note that such symptoms could accompany any number of conditions or diseases common to 19th-century Europe. “Even today, two centuries later, it would still be impossible to perform a differential diagnosis between typhus, typhoid, or paratyphoid fever based solely on the symptoms or the testimonies of survivors,” the authors wrote.

Imperial Guard button discovered during excavation

Imperial Guard button discovered during excavation. Credit: UMR 6578 Aix-Marseille Université, CNRS, EFS

Over 3,200 individual remains, almost all men between the ages of 20 and 50, were excavated from the mass grave at Vilnius. Rascovan et al. focused on 13 teeth from 13 different individuals. To compensate for the degraded nature of the 200-year-old genome fragments, co-authors at the University of Tartu in Estonia helped develop a multistep authentication method to more accurately identify pathogens in the samples. In some cases, they were even able to identify a specific lineage.

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DNA confirms these 19th century lions ate humans

animal behavior, animals, Biology, DNA analysis, forensic archaeology, lions, Security / /

For several months in 1898, a pair of male lions turned the Tsavo region of Kenya into their own human hunting grounds, killing many construction workers who were building the Kenya-Uganda railway.  A team of scientists has now identified exactly what kinds of prey the so-called “Tsavo Man-Eaters” fed upon, based on DNA analysis of hairs collected from the lions’ teeth, according to a recent paper published in the journal Current Biology. They found evidence of various species the lions had consumed, including humans.

The British began construction of a railway bridge over the Tsavo River in March 1898, with Lieutenant-Colonel John Henry Patterson leading the project. But mere days after Patterson arrived on site, workers started disappearing or being killed. The culprits: two maneless male lions, so emboldened that they often dragged workers from their tents at night to eat them. At their peak, they were killing workers almost daily—including an attack on the district officer, who narrowly escaped with claw lacerations on his back. (His assistant, however, was killed.)

Patterson finally managed to shoot and kill one of the lions on December 9 and the second 20 days later. The lion pelts decorated Patterson’s home as rugs for 25 years before being sold to Chicago’s Field Museum of Natural History in 1924. The skins were restored and used to reconstruct the lions, which are now on permanent display at the museum, along with their skulls.

Tale of the teeth

The Tsavo Man-Eaters naturally fascinated scientists, although the exact number of people they killed and/or consumed remains a matter of debate. Estimates run anywhere from 28–31 victims to 100 or more, with a 2009 study that analyzed isotopic signatures of the lions’ bone collagen and hair keratin favoring the lower range.

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Beethoven likely didn’t die from lead poisoning, new DNA analysis reveals

Biology, DNA analysis, forensic DNA, human genetics, Ludwig von Beethoven, Science / /

get the lead out —

There was also mercury and arsenic but none of the toxins likely caused composer’s death.

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(7) Portrait of Beethoven by Joseph Karl Stieler, 1820

Enlarge / Portrait of Beethoven by Joseph Karl Stieler, 1820. Toxocology analysis of the composer’s locks of hair showed high levels of lead.

Beethoven-Haus Bonn

Last year, researchers sequenced the genome of famed composer Ludwig van Beethoven for the first time, based on authenticated locks of hair. The same team has now analyzed two of the locks for toxic substances and found extremely high levels of lead, as well as arsenic and mercury, according to a recent letter published in the journal Clinical Chemistry.

“It definitely shows Beethoven was exposed to high concentrations of lead,” Paul Janetto, co-author and director of the Mayo Clinic’s Department of Laboratory Medicine and Pathology, told The New York Times. “These are the highest values in hair I’ve ever seen. We get samples from around the world, and these values are an order of magnitude higher.” That said, the authors concluded that the lead exposure was not sufficient to actually kill the composer, although Beethoven very likely did suffer adverse health effects because of it.

As previously reported, Beethoven was plagued throughout his life by myriad health problems. The composer began losing his hearing in his mid- to late 20s, experiencing tinnitus and the loss of high-tone frequencies in particular. He claimed the onset began with a fit in 1798 induced by a quarrel with a singer. By his mid-40s, he was functionally deaf and unable to perform public concerts, although he could still compose music.

Beethoven on his deathbed: lithograph by Josef Danhauser after his own drawing.

Enlarge / Beethoven on his deathbed: lithograph by Josef Danhauser after his own drawing.

Beethoven-Haus Bonn

Beethoven also had lifelong chronic gastric ailments, including persistent abdominal pains and prolonged stretches of diarrhea. By 1821, the composer showed signs of liver disease, marked by the first of two severe attacks of jaundice. These issues certainly affected his career and emotional state, so much so that Beethoven requested—via a letter addressed to his brothers—that his favorite physician examine his body after his death to determine the cause of all his suffering.

By December 1826, Beethoven was quite ill, suffering from a second bout of jaundice and swollen limbs, fever, dropsy, and labored breathing. His doctor performed several operations to remove excess fluid from the composer’s abdomen. On March 24, 1827, he purportedly said to visitors, “Plaudite, amici, comoedia finita est” (“Applaud, friends, the comedy is over”). Two days later, he died. According to his good friend Anselm Hüttenbrenner, who was present, lightning and a loud clap of thunder briefly woke Beethoven, who “opened his eyes, lifted his right hand and looked up for several seconds with his fist clenched… not another breath, not a heartbeat more.”

An autopsy identified severe liver damage (evidence of cirrhosis) as the likely cause of death and significant dilation of the auditory nerve. But what caused that liver damage or his hearing loss—or his chronic stomach complaints, for that matter? Medical detectives have been debating possible causes for nearly two centuries, drawing on the composer’s letters, diaries, and physicians’ notes for evidence, as well as reports on skeletal remains from when his body was exhumed in 1863 and 1888. But no general consensus emerged.

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